You know, after reading the post of @humanearl and the comment of @theguruasia, I felt I should be a source of encouragement to @theguruasia.
You are not alone. Just like @humanearl said in his post, he followed the wish of his mum, but later traced his ways back to his calling, and now he is living the best life he could ever live, the life he was wired for.
I too derailed when i was growing up. I wanted to be an engineer, but my dad wanted me to be a doctor. After two wasted years, I finally got back to what I loved doing, and I feel like am on top of the stars. Your dream might not fetch you as much money, but there are just certain things money can't buy. Money can't buy the satisfaction you get from following your dreams. It can't buy the joy. It can't buy the impact following your dreams will make on the life of others.
So please my brother,it is never too late. You can still make a u-turn. You must not necessarily leave you job, but you can start by following your dreams after you are back from work, and gradually you'll continue to increase until you go full time.
As long as there is life, there is hope.
All the best, and hope to see you in the land of dream fulfilers.